sched: DL replenish lagged too much rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (2 ticks this GP) idle=096c/1/0x4000000000000000 softirq=25531/25531 fqs=0 rcu: (detected by 1, t=10503 jiffies, g=17257, q=751 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6560 Comm: sed Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:check_preemption_disabled+0x49/0x120 lib/smp_processor_id.c:53 Code: 8b 0d 4b d8 15 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d 2b d8 15 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f <5d> e9 51 ca 02 00 cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 RSP: 0000:ffffc90000007b10 EFLAGS: 00000082 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 5c3fbe59d8e46a00 RDX: 0000000000000000 RSI: ffffffff8b9ec4c0 RDI: ffffffff8b9ec480 RBP: ffffffff848df52b R08: 0000000000000001 R09: 0000000000000000 R10: ffffc90000007ca0 R11: fffff52000000f96 R12: 0000000000000000 R13: ffffffff9974b490 R14: 0000000000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff88812639b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7a5c2e16c8 CR3: 0000000074d26000 CR4: 00000000003526f0 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5831 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 debug_object_activate+0xbb/0x420 lib/debugobjects.c:818 debug_hrtimer_activate kernel/time/hrtimer.c:438 [inline] debug_activate kernel/time/hrtimer.c:477 [inline] enqueue_hrtimer+0x30/0x3a0 kernel/time/hrtimer.c:1081 __run_hrtimer kernel/time/hrtimer.c:1794 [inline] __hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1058 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x2c5/0x3e0 kernel/locking/lockdep.c:5893 Code: 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 7b 2d ac 10 48 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 90 0f 0b 90 e9 5d fd RSP: 0000:ffffc90003f0f6a8 EFLAGS: 00000286 RAX: 5c3fbe59d8e46a00 RBX: ffffffff8fe8cf01 RCX: 5c3fbe59d8e46a00 RDX: 0000000000000002 RSI: ffffffff8d6ef4b7 RDI: ffffffff8b9ec4e0 RBP: ffff888024d60b80 R08: ffffc90003f0ff10 R09: 0000000000000000 R10: ffffc90003f0f7f8 R11: fffff520007e1f01 R12: 0000000000000002 R13: 0000000000000002 R14: ffffffff8dd3a860 R15: ffff888024d60000 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1169 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4191 [inline] slab_alloc_node mm/slub.c:4240 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4247 anon_vma_alloc mm/rmap.c:94 [inline] __anon_vma_prepare+0x117/0x4a0 mm/rmap.c:202 __vmf_anon_prepare mm/memory.c:3506 [inline] vmf_anon_prepare mm/internal.h:432 [inline] do_cow_fault mm/memory.c:5593 [inline] do_fault mm/memory.c:5709 [inline] do_pte_missing mm/memory.c:4234 [inline] handle_pte_fault mm/memory.c:6052 [inline] __handle_mm_fault+0x4ca8/0x5440 mm/memory.c:6195 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6364 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f7a5c3ddff2 Code: 0f 60 c0 66 0f 61 c0 66 0f 70 c0 00 48 83 fa 10 72 76 48 83 fa 20 77 12 0f 11 44 17 f0 0f 11 07 c3 0f 11 47 e0 0f 11 47 f0 c3 <0f> 11 07 0f 11 47 10 48 01 d7 48 83 fa 40 76 e7 0f 11 40 20 0f 11 RSP: 002b:00007fffcb275108 EFLAGS: 00010206 RAX: 00007f7a5c2e16c8 RBX: 0000000000000004 RCX: 00007f7a5c2eee98 RDX: 0000000000000938 RSI: 0000000000000000 RDI: 00007f7a5c2e16c8 RBP: 00007fffcb275890 R08: 00007f7a5c2e16c8 R09: 0000000000000003 R10: 0000000000000812 R11: 00007fffcb275420 R12: 00007fffcb2751b8 R13: 00007f7a5c3b15f0 R14: 00007fffcb275930 R15: 00007f7a5c2e2000 rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g17257 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=5349 rcu: rcu_preempt kthread starved for 10503 jiffies! g17257 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:I stack:27256 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245